Record-breaking German duo Lutz Eichholz and Stephanie Dietze encountered high alititudes, steep gravel fields and life threatening glaciers when they descended the Mettelhorn

Walking on the face of the Mettelhorn mountain range in Zermatt, Switzerland is challenging enough, but tackling it on a unicycle is quite remarkable.

German daredevils Lutz Eichholz and Stephanie Dietze have just completed their highest and most dangerous challenge – balancing on just one wheel, they downhill unicycled a distance of 3406m (11,174ft) across steep gravel paths, alongside sheer drops and over slippery glaciers.

“Like most mountain sports, it can be quite dangerous,” explained Eichholz after the challenge. “If you make a mistake in the wrong place you can easily fall down the cliff and face the consequences.”

In July, the fearless riders descended the Cima Ombretta Orientale Mountain in Italy, more than 3040m (10,000ft). After 16 years of riding on one wheel, Eichholz is constantly looking for his next challenge and each one offers a new rush. “I really love to do my favourite sport in the most beautiful places on earth. At the top off the mountain I feel that rush of adrenaline.”

Before each new high-altitude challenge, the duo know they may face weather changes, uneven surfaces, avalanches, snow, rain, storms and slippery glaciers. "You cannot be 100 per cent prepared for everything,” said Eichholz, “I’ve had some accidents, like a broken foot and similar injuries. But luckily I've never had anything serious – and I've never had to be in hospital for more than a few hours.”

Eichholz will not let the risks involved in this dangerous activity hold him back, “I have many plans for next season,” he said. Eichholz hopes to conquer the Andes in South America and mountain ranges in China.